/Engine/Plugins/Runtime/Metasound/Source/MetasoundFrontend/Public/MetasoundNodeRegistrationMacro.h
Use SFINAE trick to see if we have a valid constructor:
template<typename T> static uint16 TestForConstructor ( decltype(T(::[Metasound::FNodeInitData](API\Plugins\MetasoundGraphCore\FNodeInitData)()))* )